Typical switching power supplies, such as a low-side driver, may include a power transistor that is controlled by at least one driver switch. As an example, the power transistor may be activated and deactivated based on the switching of a high-side switch and/or a low-side switch. A given power transistor can be configured to conduct a large amount of current, and can thus be large in size. Therefore, it is often desirable to implement fast turn-on and turn-off times for the power transistor based on the operation of the at least one driver switch to accommodate for activation and deactivation delays of the large power transistor. As an example, a low-side switch can be activated quickly to sink a bias node of the power transistor to ground, such that capacitance (e.g., gate-source capacitance) of the power transistor can be discharged quickly.
For a switching power driver that provides power to an inductive load, flyback current can result when the inductive load is decoupled from the power source. In this context, flyback current is current that is generated from the discharge of the magnetic field energy in the inductive load, and is channeled to a low supply power (e.g., ground), such as via the bias node of the power transistor. To minimize the flyback current, the flyback current path to ground can be a high-impedance path. However, such a high-impedance path may interfere with the dissipation of the capacitive charge of the power transistor. As a result, the power transistor may not be able to be deactivated quickly. Accordingly, a switching power driver that provides power to an inductive load may have to compromise between fast deactivation and power dissipation.